全文获取类型
收费全文 | 1927篇 |
免费 | 170篇 |
国内免费 | 3篇 |
专业分类
化学 | 1313篇 |
晶体学 | 2篇 |
力学 | 57篇 |
数学 | 336篇 |
物理学 | 392篇 |
出版年
2023年 | 34篇 |
2022年 | 27篇 |
2021年 | 54篇 |
2020年 | 115篇 |
2019年 | 79篇 |
2018年 | 49篇 |
2017年 | 44篇 |
2016年 | 130篇 |
2015年 | 97篇 |
2014年 | 93篇 |
2013年 | 101篇 |
2012年 | 139篇 |
2011年 | 149篇 |
2010年 | 84篇 |
2009年 | 60篇 |
2008年 | 93篇 |
2007年 | 87篇 |
2006年 | 56篇 |
2005年 | 62篇 |
2004年 | 37篇 |
2003年 | 41篇 |
2002年 | 38篇 |
2001年 | 12篇 |
2000年 | 21篇 |
1999年 | 9篇 |
1998年 | 18篇 |
1997年 | 7篇 |
1996年 | 10篇 |
1995年 | 16篇 |
1994年 | 12篇 |
1993年 | 8篇 |
1992年 | 7篇 |
1991年 | 13篇 |
1990年 | 7篇 |
1989年 | 11篇 |
1988年 | 8篇 |
1986年 | 14篇 |
1985年 | 10篇 |
1984年 | 10篇 |
1983年 | 9篇 |
1982年 | 11篇 |
1978年 | 9篇 |
1977年 | 10篇 |
1976年 | 8篇 |
1975年 | 8篇 |
1974年 | 9篇 |
1973年 | 7篇 |
1972年 | 9篇 |
1967年 | 7篇 |
1963年 | 6篇 |
排序方式: 共有2100条查询结果,搜索用时 31 毫秒
1.
Edelsbacher Philipp Redhammer Gnther Monkowius Uwe 《Monatshefte für Chemie / Chemical Monthly》2020,151(4):543-547
Monatshefte für Chemie - Chemical Monthly - Four members of a new series of paddle-wheel copper(II) complexes bearing cyclobutanecarboxylate as bridging ligand with pyridine derived ligands in... 相似文献
2.
3.
4.
S. Schrader A. Penzkofer W. Holzer R. Velagapudi B. Grimm 《Journal of luminescence》2004,110(4):303-308
Optical, structural and morphological properties of thin films of polyparaphenylenevinylene (PPV) formed by an alkyl sulfinyl precursor route have been studied. Thin films were fabricated on an optical glass and on quartz glass either by spin-coating of the precursor solution or by layer-by-layer deposition using Langmuir–Blodgett technique. PPV precursor films were also spin-coated on gold-coated glass in order to study thin-film optical parameters by surface plasmon spectroscopy. We have been successful in forming about 40 precursor mono layers on quartz glass by Langmuir–Blodgett technique using optimized surface pressure and dipping conditions. After thermal conversion of the precursor layers good quality fluorescent PPV films of yellow colour have been obtained. Optical characterization of the films was carried out by linear absorption and emission spectroscopy, ellipsometry, and surface plasmon spectroscopy. Structural and morphological studies on the thin films were carried out by using X-ray scattering and atomic force microscopy. Wave-guided travelling-wave laser action has been achieved in a PPV film on quartz glass. The sample was transversally pumped with picosecond laser pulses (wavelength 347.15 nm, duration 35 ps). Laser emission occurred at 550 nm for pump pulse energy densities above . 相似文献
5.
6.
7.
8.
Albrecht H Binder U Harder G Lembke-Koppitz I Philipp A Schmidt-Parzefall W Schröder H Schulz HD Wurth R Donker JP Drescher A Matthiesen U Scheck H Spaan B Spengler J Wegener aD Gabriel JC Schubert KR Stiewe J Waldi R Weseler S Brown NN Edwards KW Frisken WR Fukunaga C Gilkinson DJ Gingrich DM Goddard M Kapitza H Kim PC Kutschke R MacFarlane DB McKenna JA McLean KW Nilsson AW Orr RS Padley P Patel PM Prentice JD Seywerd HC Stacey BJ Yoon T Yun JC Ammar R Coppage D Davis R Kanekal S Kwak N 《Physical review letters》1986,56(6):549-552
9.
Triolo A Russina O Hardacre C Nieuwenhuyzen M Gonzalez MA Grimm H 《The journal of physical chemistry. B》2005,109(46):22061-22066
A detailed investigation on the nature of the relaxation processes occurring in a typical room temperature ionic liquid (RTIL), namely, 1-butyl-3-methyl imidazolium hexafluorophosphate ([bmim][PF(6)]), is reported. The study was conducted using both elastic and inelastic neutron scattering over a wide temperature range from 10 to 400 K, accessing the dynamic features of both the liquid and glassy amorphous states. In this study, the inelastic fixed energy scan technique has been applied for the first time to this class of materials. Using this technique, the existence of two relaxation processes below the glass transition and a further diffusive process occurring above the glass-liquid transition are observed. The low temperature processes are associated with methyl group rotation and butyl chain relaxation in the glassy state and have been modeled in terms of two Debye-like, Arrhenius activated processes. The high temperature process has been modeled in terms of a Kohlraush-Williams-Watts relaxation, with a distinct Vogel-Fulcher-Tamman temperature dependence. These results provide novel information that will be useful in rationalizing the observed structural and dynamical behavior of RTILs in the amorphous state. 相似文献
10.
A new iterative deconvolution algorithm for the development of very high resolution Hc(I)-excited photoelectron spectra of gases is presented. The algorithm accepts as input a medium-resolution spectrum and an instrument function obtained by scanning intrinsically narrow line (e.g. the Ar2P3/2 line) under conditions identical to those used to acquire the medium resolution spectrum. The deconvolved partial spectrum of an O2H2O mixture is presented as a test case prior to presentation of results for three nitrogen lines. For comparison purposes directly obtained high-resolution spectra of the nitrogen lines are included. The shapes of the nitrogen lines are discussed within the framework of a one-center expansion theory of photoionization. The conditions under which deconvolution can be profitably applied are briefly discussed and an attempt is made to establish the deconvolution (contrary to still popular belief) is not in any way equivalent to curve fitting. 相似文献